The instant invention relates to postage metering systems utilizing portable postage vaults, and more particularly to a method and apparatus for ensuring that revenue generated by the portable postage vaults is properly credited to the specific post office which actually initiates the processing of any specific mailpiece.
Postage meters of both the electronic and mechanical variety have conventionally had all of the accounting and printing control structure contained in a secure single housing in order to protect against tampering. Recently, however, advances in microelectronics, digital printing, and encryption techniques have led to the design of modular postage metering systems such as those disclosed in U.S. Pat. No. 4,802,218 issued to Wright et al. and U.S. Pat. application Ser. No. 08/702,077 filed Aug. 23, 1996 now U.S. Pat. No. 5,812,400 and entitled "ELECTRONIC POSTAGE METER INSTALLATION AND LOCATION MOVEMENT SYSTEM" which is hereby incorporated by reference. In these newer systems, the postage accounting vault is a portable device, such as a smart card, which can be removably inserted into a base module containing the metering system interface controls and a removable printhead module. Since all of the components are easily accessible and not contained within a single secure housing, security is provided via encrypted communications between the various metering system modules. Moreover, it has been proposed to utilize encrypted information, which is printed together with the postage indicia for increasing security relative to fraudulently printed postage indicia. That is, the printed encrypted information on any mailpiece can be subsequently scanned and analyzed by a postal authority to determine the authenticity of the printed indicia on the selected mailpiece. Thus, while the scanning of every single mailpiece being processed may not be considered practical, random sampling of individual mailpieces would likely identify any large scale fraudulent indicia printing operation.
The use of the above-discussed modular metering systems has provided great flexibility in postage meter system design. For example, individual accounting and printing modules can be easily replaced, if defective, without having to return the entire metering system to the postal authority. Moreover, the enhancements in encrypted security techniques have even led to the development of personal computer metering concepts where non-dedicated computer printers are used to print the postage indicia. In addition, where portable accounting devices are used, the metering system user is provided with a great deal of operational flexibility because any number of portable accounting devices can be inserted into any single base module for the purpose of printing postage. Thus, a company can have a central base module and allocate individual portable postage vaults to different departments. Since each portable vault can be controlled via software to have a postage fund limit, flexibility is provided in that individual departments can easily place postage on items to be mailed while individual accounting and postage expenses are carefully monitored in each portable vault. This same concept can also be used to locate a base module at a central location in a community, such as a convenience store. Individuals could then obtain portable vaults for use in the central base module so that postage could be applied to their individual mailpieces. Since the postage is prepaid for and accounted for in the individual portable vaults, the mailing of individual pieces of mail (or even a batch of mail) becomes easier for individuals without requiring them to procure or rent the entire base module.
While the above use of multiple portable vaults capable of being utilized in any base module is considered extremely advantageous for the reasons discussed above, it also presents a significant accounting problem for the United States Postal Service. That is, in the United States, postage meters are registered to a particular user for use in a specified zip code location. Thus, the existing postage meter tracking structure associates a specific meter serial number with a specific zip code location. Since mailpieces having an indicia imprinted thereon are only supposed to be mailed from the local post office for the zip code that matches the meter serial number, all postage revenue generated by a specific postage meter is automatically credited to the local post office which is assumed to have initiated the mailing process. This system has been considered adequate for properly crediting postage revenue to individual post offices because, prior to the proposed use of portable accounting vaults, single housed postage meters were not considered as being portable items. Thus, once the older single housed meters were installed, they would print indicia on mailpieces within the designated zip code location and all such mailpieces would typically be mailed at the corresponding local post office. However, the use of portable vaults potentially creates problems with the desired revenue accounting desired by the United States Postal Service. That is, even if each portable vault has a serial number associated therewith, which serial number is linked in the conventional manner to a specific zip code, these portable vaults are easily transported throughout the country since they are no bigger than a conventional credit card. Accordingly, if someone has an authorized portable postage vault and they use it in a base module located in a zip code region different from the zip code region associated with the authorized portable postage vault, a postage indicia will still be printed on the mailpiece. However, in this situation, since the Postal Authority accounting infrastructure is set up to assign all revenue generated by each portable postage vault to the zip code location it is assigned to, the post office that actually initiated the mailpiece mailing would not receive revenue credit.
Thus, it is desirable to provide a postage metering system which recognizes some of the benefits discussed above in connection with the use of portable postage vaults while at the same time reasonably ensuring the proper crediting of postage revenue to the post office that actually initiates the mailing process.